Hubble Telescope Spots an Intergalactic String of Pearls

Astronomy and Space Science

Alumni

No jeweler on the planet can beat the string of pearls spotted by the Hubble Space Telescope: The merger of two elliptical galaxies has created a "necklace" of infant stars stretching for 100,000 light-years.

NASA / ESA / RIT / HUBBLE HERITAGE

Jul. 10, 2014

Alan Boyle

Everything about this picture is big: The stellar string would stretch from one end of our Milky Way galaxy to the other, between two galaxies that are both three times wider than our own. The galaxies are contained in a cluster known as SDSS J1531+3414, a formation that's so massive its gravitation field bends the images of background galaxies into bluish arcs.

When the images were acquired, astronomers assumed the chain of stars was merely an illusion created by the galaxy cluster's gravitational lens. But follow-up observations using the Nordic Optical Telescope in the Canary Islands ruled out that hypothesis.

"We were surprised to find this stunning morphology, which must be very short-lived," Grant Tremblay of the European Southern Observatory said in a news release from the Space Telescope Science Institute. "We've long known that the 'beads on a string' phenomenon is seen in the arms of spiral galaxies and in tidal bridges between interacting galaxies. However, this particular supercluster arrangement has never been seen before in giant merging elliptical galaxies."

Tremblay compared the phenomenon to "two monsters playing tug-of-war with a necklace."